Georges etienne sire



G. E. SIRE.

GYROSGOPE.

Patented N0v.3, 1891.

(No Model.)

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UNTTED STATES PATENT OFFICE.

GEORGES ETIENNE SIRE, OF BESANQON, FRANCE.

GYROSCOPE.

SPECIFICATION forming part of Letters Patent No. 462,512, dated November3, 1891.

Application filed June 8, 1891. Serial No. 395.438. (No model.) Patentedin France June 23, 1890, No. 206,474-

To to whom, it may concern;-

Be it known that I, GEORGES ETIENNE SIRE, a citizen of the Republic ofFrance, and a resident of the city of Besangon, in the Department ofDoubs, Republic of France, have invented certain new and usefulImprovements in Gyroscopes, (for which Letters Patent were granted inFrance June 23, 1890, No. 206374,) of which the following is aspecification.

My invention relates to improvements in gyroscopes; and the object of myinvention is to provide a simple device which may be used as ascientific toy and as an instrument of mechanical demonstration.

To this end my invention consists in a gyroscope constructedsubstantially as hereinafter described and claimed.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar letters of reference indicatecorresponding parts in all the figures.

Figure 1 is a side elevation of the gyroscope embodying my invention.Fig. 2 is a plan view of the same, and Fig. 3 shows the position of thegyroscope when in operation.

A heavy metallic disk T has an axis A extending centrally through it,which axisterminates in conical points 00 g, which turn in the bearings(L a, and these are secured in opposite sides of an annular block 0,which block is cut away in the center, as shown in Fig. 1, to receivethe disk '1.

It is necessary in the operation of the gyroscope to transmit a rapidrotary motion to the disk T, and for this purpose a small string isused, which may be wound on one end of the axis A and the end of thestring thrust through the hole 25 in the axis, or it may be wound uponthe other end and may terminate in a ring, which may be secured to theprojecting pin it of the axis. It will be seen that by winding a stringseveral times around the axis and then quickly withdrawing it the axiswill be rapidly revolved, thus rotating the disk '1, and the inertia ofthe disk will keep it in motion for some time.

The block 0 is substantially like a pulley and has a groove g in itsface, and fixed to any point in the groove is a cord 9, which is adaptedto be wound several times around the grooved portion of the block, andthe cord terminates at its free end in a ring, which is adapted to beplaced upon the finger. The ring is not shown in the drawings; but as itis a common practice to provide a winding cord with a ring it is thoughtunnecesary to show it. If the cord 7' is wound several times around theblock C and the block is dropped when the disk T is not in motion, theblock will drop of its own weight and will unwind with a certainrapidity; but if the disk T is first caused to turn rapidly and theblock is then dropped the block will continue to be suspended withoutunwinding from the cord, and the entire device will take a movement ofprecessionthat is, it will turn in a certain direction around thesuspension-cord, while the axis of rotation of the disk will form anangle with this cord; but gravity acting on the device will cause theblock to unwind gradually, and this will take place most parallel to thesuspensioncord. At this moment the block fails a very little, and thewhole device again turns around the suspension-cord, but in an oppositedirection to that in which it turned before.

Gravity, acting constantly on the device, causes it to descend little bylittle, the block turning and unrolling little by little until the axisof rotation of the disk approaches a position parallel to the cord ofsuspension, as before. At this instant the device falls a little again,and the movement of precession is immediately reversed. This reversemovement is produced at each half-revolution of the blockthat is, thenumber of reversions is double the number of turns of the cord aroundthe grooved portion of the block.

Having thus fully described my invention,

ters Patent- 1. A gyroscope comprising an annularblock having a groovedface and a central recess, a suspension-cord secured in the groove ofthe block, and a revoluhle disk mounted in the recess of the block,substantially as shown and described.

2. A gyroscope comprising a block having a central recess therein andhaving a grooved I claim as new and desire to secure by Letwhen the axisof rotation of the disk is alfaeegasuspension-cord secured in thegrooved enee of two witnesses, this 8th day of April, portion of theblock, and an axis pivoted in 1891. diametrically-opposite sides of therecess in V 1 T the block, said axis carrying a disk, snbstan- GEORGESLHENBE SIRE 5 tially as shown and described. W'itnesses:

In testimony that I claim the foregoing as ROBT. M. HOOPER,

my invention I have signed my name, in PIBS- l ARTHUR GOOD.

